Function text_transform 

pub fn text_transform(m: Affine, tr: Rect, rotation: f64) -> Affine

Where text laid out in text rect tr is drawn, for a shape drawn with m (shape-local → output): m, without mirroring, then the layout’s rotation about the rect’s centre.

Flips mirror a shape’s geometry, never its text. When m reflects (flipH or flipV, the shape’s own or a group’s) the text rect keeps its mirrored place and the text is mirrored back about the rect’s centre: a flipH shape’s text stays readable and a flipV shape’s text is turned 180° (both flips: 180°), as in PowerPoint. Rendering, hit testing and the caret all use this.